This is a concrete derived type whose instances can be used to define/request the default uniform random number generator (RNG) of the Fortran standard.
More...
This is a concrete derived type whose instances can be used to define/request the default uniform random number generator (RNG) of the Fortran standard.
This type does not currently hold any components.
It is merely used to signal/request the use of the intrinsic Fortran RNG.
The Fortran programming language offers a single mechanism through the intrinsic procedure random_seed(size = size, put = put, get = get) to set the seed of the intrinsic uniform random number generator of Fortran random_number(harvest).
However, the internal implementation of the random number generator can vary from compiler to another.
Furthermore, the size and requirements for the initial state (seed) can be also different across compilers.
As such, Fortran programming language also offers a new intrinsic procedure random_init(repeatable, image_distinct).
-
If
repeatable = .true., the seed is set to the same processor-dependent value each time random_init(repeatable = .true., ...) is called from the same image.
The program is, therefore, guaranteed to generate the same random number sequence after each call to random_init().
The term same image means a single instance of program execution.
The sequence of random numbers is different for repeated execution of the program.
If it is .false., the seed is set to a processor-dependent value.
-
If
image_distinct = .true., the seed is set to a processor-dependent value that is distinct from th seed set by a call to random_init() in another (Coarray) image.
If it is image_distinct = .false., the seed is set to a value that does not depend which image called random_init().
The Fortran intrinsic random_init() apparently does guarantee the generation of the same random sequence in multiple independent executions of the program.
This requires setting the RNG seed explicitly at the beginning of each program execution.
The rngf_type aims to facilitate the above goal by offering a single interface that combines random_init() and random_seed() intrinsic routines.
- Parameters
-
| [in] | seed | : The input scalar of type integer of default kind IK, containing a positive integer that serves as the starting point to generate the full RNG seed.
Specify this input argument if you wish to make random simulations reproducible, even between multiple independent runs of the program compiled by the same compiler.
(optional. If missing, it is set to a value determined by the current date and time.) |
| [in] | imageID | : The input positive scalar integer of default kind IK containing the ID of the current image/thread/process.
This can be,
-
The Coarray image ID as returned by Fortran intrinsic
this_image() within a global team of Coarray images.
-
The MPI rank of the processor (plus one) as returned by the MPI library intrinsic
mpi_comm_rank().
-
The OpenMP thread number as returned by the OpenMP library intrinsic
omp_get_thread_num().
-
Any (positive) integer that uniquely identifies the current processor from other processes.
The image/process/thread ID can be readily obtained by calling getImageID.
This number will be used to set the RNG seed uniquely on each processor.
(optional. If missing, the RNG seed will be set identically on all images.) |
- Returns
rng : The output scalar object of type rngf_type.
Possible calling interfaces ⛓
type(rngf_type) :: rng
rng
= rngf_type(seed
= seed, imageID
= imageID)
Generate and return an allocatable array of rank 1 containing the state vector of the Fortran default...
This module contains classes and procedures for computing various statistical quantities related to t...
This module defines the relevant Fortran kind type-parameters frequently used in the ParaMonte librar...
integer, parameter IK
The default integer kind in the ParaMonte library: int32 in Fortran, c_int32_t in C-Fortran Interoper...
This is a concrete derived type whose instances can be used to define/request the default uniform ran...
- Note
- This generic interface does not aim to replicate the behavior of the Fortran intrinsic
random_init() but rather to extend it.
If you wish to reset the RNG seed to a reproducible seed without specifying a scalar reference value for it via this generic interface, simply call random_init(repeatable = .true., ...).
However, unlike random_init(), this generic interface can guarantee reproducibility of RNG sequences within and between multiple program runs in serial or parallel Coarray/MPI/OpenMP, all compiled by the same compiler.
- See also
- rngf
isHead
getUnifCDF
getUnifRand
setUnifRand
getUnifRandState
setUnifRandState
rngu_type
rngf_type
splitmix64_type
xoshiro256ssw_type
getUnifRandStateSize
Example usage ⛓
12 type(rngf_type) :: rng
14 type(display_type) :: disp
19 call disp%show(
"!%%%%%%%%%%%%%%%%%%%%%%%")
20 call disp%show(
"! Set a random RNG seed.")
21 call disp%show(
"!%%%%%%%%%%%%%%%%%%%%%%%")
32 call disp%show(
"!%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%")
33 call disp%show(
"! Set the current RNG seed based on the input scalar `seed` and return a copy of seed vector.")
34 call disp%show(
"!%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%")
38 call disp%show(
"rng = rngf_type(seed = 12345_IK)")
45 call disp%show(
"!%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%")
46 call disp%show(
"! Set the current RNG seed on each image distinctly based on the current date and time and and the image ID and return a copy of seed vector.")
47 call disp%show(
"!%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%")
51 call disp%show(
"rng = rngf_type(imageID = getImageID())")
58 call disp%show(
"!%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%")
59 call disp%show(
"! Set the current RNG seed on each image distinctly based on the input scalar `seed` and and the image ID and return a copy of seed vector.")
60 call disp%show(
"!%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%")
64 call disp%show(
"rng = rngf_type(seed = 12345_IK, imageID = getImageID())")
71 call disp%show(
"!%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%")
72 call disp%show(
"! Reset the RNG seed deterministically on each image distinctly based on the input scalar `seed` and and the image ID and return a copy of seed vector.")
73 call disp%show(
"!%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%")
77 call disp%show(
"rng = rngf_type(seed = 12345_IK, imageID = getImageID())")
81 call disp%show(
"getUnifRand(1, 100, 10)")
83 call disp%show(
"rng = rngf_type(seed = 12345_IK, imageID = getImageID())")
87 call disp%show(
"getUnifRand(1, 100, 10)")
89 call disp%show(
"rng = rngf_type() ! random RNG seed reset.")
93 call disp%show(
"getUnifRand(1, 100, 10)")
Generate and return a scalar or a contiguous array of rank 1 of length s1 of randomly uniformly distr...
This is a generic method of the derived type display_type with pass attribute.
This is a generic method of the derived type display_type with pass attribute.
This module contains classes and procedures for input/output (IO) or generic display operations on st...
type(display_type) disp
This is a scalar module variable an object of type display_type for general display.
integer, parameter LK
The default logical kind in the ParaMonte library: kind(.true.) in Fortran, kind(....
integer, parameter SK
The default character kind in the ParaMonte library: kind("a") in Fortran, c_char in C-Fortran Intero...
This module contains procedures and generic interfaces for facilitating parallel computations or comp...
integer(IK) function getImageID()
Generate and return the ID of the current Coarray image / MPI process / OpenMP thread,...
Generate and return an object of type display_type.
Example Unix compile command via Intel ifort compiler ⛓
3ifort -fpp -standard-semantics -O3 -Wl,-rpath,../../../lib -I../../../inc main.F90 ../../../lib/libparamonte* -o main.exe
Example Windows Batch compile command via Intel ifort compiler ⛓
2set PATH=..\..\..\lib;%PATH%
3ifort /fpp /standard-semantics /O3 /I:..\..\..\include main.F90 ..\..\..\lib\libparamonte*.lib /exe:main.exe
Example Unix / MinGW compile command via GNU gfortran compiler ⛓
3gfortran -cpp -ffree-line-length-none -O3 -Wl,-rpath,../../../lib -I../../../inc main.F90 ../../../lib/libparamonte* -o main.exe
Example output ⛓
9-1276477989,
-1843897389,
+569289352,
-425947020,
+1291547335,
+1917828995,
-1604155780,
-1029633801
19-930397057,
-1271367333,
-839688912,
+1099379960,
+310102611,
+1239277010,
+1840798532,
+493908163
29+2097967764,
-1476900477,
-1499919547,
+643828201,
-1665671295,
+1611227948,
-1146307549,
+2070809301
39-930397057,
-1271367333,
-839688912,
+1099379960,
+310102611,
+1239277010,
+1840798532,
+493908163
49-930397057,
-1271367333,
-839688912,
+1099379960,
+310102611,
+1239277010,
+1840798532,
+493908163
51+44,
+74,
+42,
+71,
+33,
+82,
+43,
+18,
+66,
+10
54-930397057,
-1271367333,
-839688912,
+1099379960,
+310102611,
+1239277010,
+1840798532,
+493908163
56+44,
+74,
+42,
+71,
+33,
+82,
+43,
+18,
+66,
+10
59-284023472,
-399571742,
-1798873524,
-698507775,
+1861790304,
-1180032139,
+1683890495,
+928970421
61+43,
+86,
+21,
+45,
+45,
+73,
+61,
+76,
+12,
+14
Final Remarks ⛓
If you believe this algorithm or its documentation can be improved, we appreciate your contribution and help to edit this page's documentation and source file on GitHub.
For details on the naming abbreviations, see this page.
For details on the naming conventions, see this page.
This software is distributed under the MIT license with additional terms outlined below.
-
If you use any parts or concepts from this library to any extent, please acknowledge the usage by citing the relevant publications of the ParaMonte library.
-
If you regenerate any parts/ideas from this library in a programming environment other than those currently supported by this ParaMonte library (i.e., other than C, C++, Fortran, MATLAB, Python, R), please also ask the end users to cite this original ParaMonte library.
This software is available to the public under a highly permissive license.
Help us justify its continued development and maintenance by acknowledging its benefit to society, distributing it, and contributing to it.
- Copyright
- Computational Data Science Lab
- Author:
- Amir Shahmoradi, September 1, 2017, 12:00 AM, Institute for Computational Engineering and Sciences (ICES), The University of Texas Austin
Definition at line 2837 of file pm_distUnif.F90.
1.9.3